Field
Embodiments of the disclosure generally relate to a plasma profile control plate utilized in a plasma processing chamber for forming a plasma with uniform distribution, and more particularly, a plasma profile control plate with individual controllable cells to locally alter and control plasma distribution across a substrate surface disposed in a plasma processing chamber in a semiconductor manufacturing process.
Description of the Background Art
Reliably producing submicron and smaller features is one of the key technologies for the next generation of very large scale integration (VLSI) and ultra large scale integration (ULSI) of semiconductor devices. However, as the miniaturization of circuit technology is pressed, the shrinking dimensions of interconnects in VLSI and ULSI technology have placed additional demands on the processing capabilities. The multilevel interconnects that lie at the heart of this technology require precise processing of high aspect ratio features, such as vies and other interconnects. Reliable formation of these interconnects is very important to VLSI and ULSI success and to the continued effort to increase circuit density and quality of individual substrates.
As circuit densities increase for next generation devices, the widths of interconnects, such as vias, trenches, contacts, gate structures and other features, as well as the dielectric materials therebetween, decrease to 45 nm and 32 nm dimensions, whereas the thickness of the dielectric layers remain substantially constant, with the result of increasing the aspect ratios of the features.
Many semiconductor devices are processed in the presence of a plasma. The plasma may be easily ignited in processing chambers that utilized capacitively coupled power, inductively coupled power, or microwave power to energize the gases forming the plasma. However, the plasma generated in the processing chamber may often not be uniformly distributed all across an entire surface of the substrate. For example, the plasma may not always extend to an edge of the substrate, resulting in different edge to center processing rates. Non-uniform plasma distribution at different locations across the substrate surface may result in asymmetrical or non-uniform processing profiles of the target-processing material disposed on the substrate. As such, non-uniform plasma distribution across the substrate surface may eventually result in defects, such as feature deformation, line edge roughness or tapered top portion of the features translated into the target-processing material.
Therefore, there is a need for an improved method and apparatus for uniform plasma distribution control across a substrate surface during a plasma process.